Test System Setup and Benchmarks
First off, we’d like to once again note that we did not use a reference 8800/9800 GT for our tests and instead chose the factory overclocked Gigabyte 8800 GT TurboForce edition. With a 100 MHz graphics processor overclock to 700 MHz and a 20 MHz memory overclock to 920 MHz, Gigabyte’s 8800 GT sports one of the highest factory overclocks available for an 8800/9800 GT.
Because we’re testing both SLI and CrossFire dual-card configurations, we can’t use the same platform for both. The only platform that is both SLI- and CrossFire-certified is Intel’s new X58 Core i7 chipset. Instead of using that one, though, we used a DFI Lanparty X38 for CrossFire testing and an MSI P7N Platinum for SLI testing.
This presents us with a bit of a challenge in that Intel’s X38 chipset provides true 16x PCIe bandwidth to both graphics card slots when used in CrossFire mode. Unfortunately, Nvidia’s 750i chipset only allows for 16x PCIe bandwidth for a single card, and when two cards are used in an SLI configuration, both graphics slots are allotted 8x PCIe bandwidth each.
However, there’s not really any problem at all. The 750i chipset offers PCIe 2. 0 signaling, and two 8x PCIe slots should deliver plenty of bandwidth for a couple of 8800 GTs in SLI configuration. Thomas Soderstrom’s recent article PCI Express and CrossFire: Scaling Explored demonstrated that even two powerful Radeon HD 4870 cards were not significantly hampered when each card had 8x PCIe 2. 0 bandwidth compared to 16x PCIe 2. 0 bandwidth for each card. It appears that if both motherboards are up to the PCIe 2. 0 standard, there won’t be a notable performance difference.
Furthermore, the Nvidia 750i chipset makes much more sense to compare to an X38 motherboard when price is concerned. They both can be found for about $160. When you consider the cheapest dual-slot 16x PCIe SLI solution is the 780i chipset priced between $200 and $300, the 750i is a much more realistic comparison within a budget.
With this in mind, the Radeon HD 4830 cards were tested on the DFI Lanparty X38 motherboard, while the GeForce 8800 GT cards were tested on the MSI P7N Platinum 750i motherboard. Both motherboards were fitted with the exact same E8500 processor and PNY DDR2 memory. We swapped a single 8800 GT and 4830 between the motherboards and ran a few benchmarks to ensure that the results were similar on either platform.
Both the PowerColor Radeon HD 4830 and the Sapphire Radeon HD 4830 sport the exact same clock speeds and GPU, and it quickly became apparent in our testing that they would also produce the same results. Therefore, to minimize confusion in the benchmark charts, we have only included one representation of Radeon HD 4830 performance in both single-card and CrossFire configurations. The exception to this is, of course, where overclocking and noise levels were tested.
As an added bonus, we included the fastest video card currently available, the Radeon HD 4870 X2, in our benchmarks to see where the performance of these cheaper solutions fit in relation.
Now, let’s examine the test systems:
|Component||CrossFire System||SLI System|
|CPU||Intel Core 2 Duo E85003. 16 GHz, FSB-1333, 6 MB Cache||Unchanged|
|CPU Cooler||Xigmatek HDT-S1283||Unchanged|
|Motherboard||DFI Lanparty X38Intel X38, BIOS 6. 00 (10/03/2008) Northbridge Voltage: 1. 30 V||MSI P7N Platinum Nvidia 750i, BIOS 1. 2 (7/11/2008)|
|RAM||4. 0 GB PNY XLR8 2x 2, 048 MB, DDR2-800, CL 4-4-4-12 at 1. 80 V||Unchanged|
|Graphics||Radeon 4830 RV770LE GPU , 575 MHz512 MB GDDR3 900 MHz||Gigabyte GeForce 8800 GTNvidia G92 GPU, 700 MHz512 MB GDDR3 920 MHz|
|Hard Drives||Western Digital Caviar black 640GD640 GB, 7, 2000 RPM, 32 MB Cache||Unchanged|
|Network||Integrated Gigabit Networking||Unchanged|
|Power||Antec Neo 650W ATX 12 V/EPS 12 V, 57A between three 12 V Rails||Unchanged|
|Optical||LITE-ON 20X DVD±R SATA Model iHAS120-04||Unchanged|
|Software and Drivers|
|Operating System||Windows Vista Ultimate 32-bit, SP1||Unchanged|
|Graphics Driver||Catalyst 8. 10 32-bit Edition||Nvidia Forceware 180. 48|
Now that you have an idea about the system settings we used, have a quick gander at the games and benchmark settings we applied before digging into the nitty-gritty of the benchmarking charts:
|Benchmarks and Settings|
|Crysis:||Version: 1. 2. 1Video Quality: Very High DetailsDemo: CPU-Benchmark + Tom’s Hardware Tool|
|Far Cry 2:||Version : 1. 0. 0Video Quality: Ultra HighDemo: FC2 benchmark Tool|
|Supreme Commander Forged Alliance||Version : 1. 5. 3599Video Quality: Highest SettingsDemo: WallaceTX_006_006Benchmark: Fraps 2. 9. 4–Build 7037|
|World in Conflict||Version : 1. 0. 0. 9Video Quality: Very High detailsDemo : Game-Benchmark|
|Race Driver GRID||Version : 1. 0Highest DetailsGameplay: Detroit Pro-tuned race, rear starting position|
|3DMark Vantage||Version : 1. 02|